Dental plaque disclosing compositions

ABSTRACT

Disclosing agents for use in control of dental plaque. The agents are compositions comprises of FDC Red No. 3 and FDC Blue No. 1; FDC Red No. 3 and FDC Green No. 3 and FDC Red No. 3 and Hercules Green Shade 3.

This is a continuation of application Ser. No. 343,764, filed Mar. 22,1973, now abandoned, which is a divisional application of Ser. No.109,054, filed Jan. 22, 1971, now U.S. Pat. No. 3,723,613.

This invention relates to novel disclosing agents for use in theimprovement of oral hygiene practices. More specifically the inventionpertains to combinations of dyes; FDC Red No. 3 and FDC Blue No. 1; FDCRed No. 3 and FDC Green No. 3; FDC Red No. 3 and Hercules Green Shade 3for employment as disclosing agents in the control of dental plaque.

Dental Plaque is a well-organized structure which forms on toothsurfaces and restorations. It consists mainly of bacteria surrounded bya matrix derived primarily from saliva and the bacteria themselves.Plaque differs from other soft tooth deposits such as materia alba andfood debris in that it has a definite architecture and cannot be flushedaway by rinsing with water.

It is well established that dental plaque plays a major role in theetiology of periodontal diseases and caries. Although the exact mannerin which plaque contributes to these disease states is not known atpresent, it is appreciated that effective and thorough removal of thesedeposits is absolutely essential for oral health. Accordingly it isdesirable that an effective plaque control program be established aspart of the treatment plan for every dental patient. For this program tobe effective the patient must be motivated to carry out thorough dailyplaque control techniques. Motivation can be achieved, however, only byestablishing goals that are meaningful and attainable by the patient.Experience has shown that most patients would not be sufficientlymotivated to practice good oral hygiene if they were simply told thatplaque is a bacterial colony growing on their teeth; that plaqueproduces gingival disease and caries and must be removed daily. However,the entire concept of what plaque is and what it does to tissue can bemade vital and important to the patient by "visualization" whereby everypatient is shown his plaque in situ and under the phase contrastmicroscope. The patient may also observe the diseased gingival areas andtheir juxtaposition to the places of plaque accumulation. These visualdemonstrations serve two main purposes. First, it shows the patient thathe does indeed have these dangerous bacterial deposits called plaques onhis teeth. Secondly, by microscopic visualization, he sees that thoseinnocent looking masses are composed of millions of living bacteria ofdiffering shapes; some even having the ability to move about. Experiencehas shown that the technique of visualization of plaque generates inpatients a true interest in plaque, and an obvious and apparent concernfor its prompt removal.

Since plaque is translucent or tooth-colored, it is necessary that it beappropriately stained in order for it to be made visible. Disclosingdyes have been in use for over 50 years. Many substances have been used,e.g. iodine, basic fuchsin neutral red, etc. Some dyes previously triedby the prior art could not be used because they were suspectedcarcinogens, others appeared in the urine, and taste was a drawback tomany materials.

Since its development in 1963, a disclosing tablet containing FDC No. 3as the staining agent has been widely employed as a disclosing agent tostain plaque. One of the reasons the dye was so widely accepted wasbecause it met the criteria established at that time for an effectivedisclosing medium; namely, that it should have a pleasing shade of red.However, with regular use of the FDC Red No. 3 tablet, it becameabundantly clear that the "pleasing shade of red" adversely affected theutility of the wafer. The plaque interproximally and at the gingivalmargin, especially in the posterior areas, could not easily be seenbecause of poor contrast between the gingiva and the stained plaque.Accordingly, the use of a red disclosing dye reveals that red is thewrong color since plaque that has been stained red is extremelydifficult to see due to poor contrast with the oral tissues, especiallyin the back areas of the mouth and between the teeth. It should be notedthat it is these precise areas which are the most prevalent sites ofcaries and periodontal disease.

A disclosing agent having all the desirable properties of the currentred media, but possessing, however, a color which would be in sharpcontrast to the gingival tissues would vastly improve the effectivenessof such a product. The continuing search for an improved disclosing dyepreparation has led to the development of the blue dye medium of theinvention which provides a two-tone dye test for dental plaque.

The novel dyes of the invention not only stain plaque a color whichcontrasts well with the tissues and teeth, thus making plaque visibleeven in the hard to see places, but they possess the property ofselective differential staining and thereby permit a distinction to bemade between areas of old thick accumulations and thin recent deposits.It has been well documented in dental literature that it is thick plaquedeposits which are generally associated with periodontal disease andexhibit the anaerobic flora seen in periodontal pockets. In other words,thick old plaques are probably more pathogenic than the new deposits.

The novel dyes of the invention are unique in that by color alone thethird dimension of plaque, its age and thickness, can be readilyestimated. Thick plaques stain blue and thin plaques stain red. Sinceold and new plaques have their own characteristic microbial morphology,the bacterial types can be also judged by color differentiation usingthe dyes of the invention. Utilizing the novel two-tone dye test fordental plaque the patient can, for the first time, judge for himselfwhether he has been practicing effective plaque removal by notingwhether any plaque deposits which may be stained are either red or blue.If he consistently misses certain areas they will be considerablythicker and therefore stained blue. If he has been doing a thorough andeffective job of plaque control, he will either show no stain pickup orif he has thin deposits they will stain red.

The dentist can also use this dye test to obtain virtually aquantitative evaluation of the effectiveness of the patients plaquecontrol.

Additionally, the dyes are a useful tool in dental research. For thefirst time the extremely important third dimension of plaque, itsthickness can be noted by color differential and this informationrecorded in a photograph. Studies that have been conducted heretofore toevaluate the effectiveness of antiplaque agents and oral hygiene aidsusing the prior art erythrosine have failed to convey the informationabout plaque thickness.

In the following study patients were selected at random and their teethwere stained with a representative dye of the invention (FDC Red No. 3and FDC Green No. 3). Kodachromes were taken of these stained areas fromwhich plaque was to be removed for microscopic examination. At all timesplaque samples were taken from teeth that showed red and blue plaque onthe same tooth. This was done to eliminate any variation in plaquebacterial morphology that could exist between one tooth and another.Each plaque colony was dissected with the tip of a fine curette. Thesamples were placed on a slide, suspended in Ringers Solution, andexamined and photographed through a phase contrast microscope at 400 ×and 1000 ×. According to the invention it is now possible to distinguishbetween old thick plaque and new thin plaque based on the distinctivecolor each takes with the novel dye of the invention.

Generally, blue plaque shows the following clinical and microscopicfeatures:

1. Considerably greater thickness than red plaque.

2. High degree of architectural organization. Cocci, rods and/orfilaments arranged in parallel rows forming fan-shaped patterns. Theserays were perpendicular to the tooth but this pattern was broken at thetime of sample removal.

3. Filaments intertwined forming a mesh work.

4. Motility -- present in some blue plaques.

5. Spiral organisms and vibrios.

Red plaques are distinguished by the following:

1. Extreme thinness -- to the extent that sometimes it was hard toobtain sufficient material for examination.

2. Low density of organisms.

3. No evidence of any orderly architecture.

4. No motility.

5. No filaments, spiral organisms or vibrios.

On some teeth treated with the dye it was also possible to distinguishan intermediate zone between the red and blue areas that had a definitepurple color. This intermediate area tended to look more like blueplaque than red plaque but the thickness of this plaque was less thanthat of blue plaque.

Close examination of the Kodachromes revealed some interesting facts.Plaque colonies growing on a tooth surface displayed a central raisedblue mass surrounded by a red and/or purple peripheral zone which waslower than the central mass. The red zones of adjacent colonies tendedto fuse forming red fields peppered with blue raised areas. Those toothsurfaces that were not covered with plaque did not show the dye at all.It should be noted that patients treated with the dye do not find theblue color objectionable or the taste unpalatable. The blue color fadesquickly from teeth, restorations and tissues with simple water rinsesand brushing. In addition, stains are easily removed from laundry orplumbing fixtures.

The dyes of the invention find particular value as research anddiagnostic tools. They can be used in evaluating antiplaque agents, orplaque control techniques and devices by providing vital informationabout the third dimension of plaque, its thickness. Prior art disclosingdyes have not been able to supply this information, thus severelylimiting the value of those studies conducted to measure theeffectiveness of plaque removal.

The relative ratio of one dye to the other in formulating the dyecompositions of the invention is not critical and the unobvious two-toneproperties may be achieved by employing for each part by weight of FDCRed No. 3 from about .1 to about 4 parts by weight of either FDC GreenNo. 3, FDC Blue No. 1 or Hercules Green Shade 3. A preferred ratio wouldinvolve one to two parts by weight of the latter for each part by weightof FDC Red No. 3.

Where the dye is to be used in the form of a solution, the concentrationof the dye is not critical and may vary from about 600 to 1200 mg. per100 ml. of solution. If one desires to utilize the dyes as tablets orwafers, the amount of dye included in each tablet or wafer is notcritical and may vary from about 20 mg. to about 100 mg. per dosageunit.

A representative example of a combination of FDC Red. No. 3 and FDCGreen No. 3 that may be used in the practice of the invention is asfollows:

    ______________________________________                                        FDC Red No. 3        200    mg.                                               FDC Green No. 3      400    mg.                                               Surfactant (Tween 20)                                                                              0.1    ml.                                               Tap water            60     ml.                                               ______________________________________                                    

The formulation is painted on the teeth and gingiva, retained a fewseconds and rinsed off with a small amount of water. Newly formed plaquestains red whereas old plaque stains deep blue or purple.

The manner by which the dye is made available to the mouth area is notcritical and will vary according to patient acceptance and convenience.For example, in addition to painting on the teeth the novel dye can beformulated as a chewable tablet, wafer, powder, lozenges, aerosol,liquid concentrate, etc.

Examples directed to the preparation of such formulations are asfollows:

    ______________________________________                                        Chewable Tablets or Wafers                                                                              Grams                                               Mannitol, granular        .905                                                Flavoring oils, spray dried in gum acacia                                                               .025                                                Calcium stearate          .010                                                FDC Red No. 3             .020                                                FDC Green No. 3           .040                                                                          1.000                                               Lactose, spray dried      .855                                                Flavoring oils, spray dried in gelatin                                                                  .020                                                Magnesium stearate        .014                                                FDC Red No. 3             .020                                                FDC Green No. 3           .040                                                Saccharin                 .001                                                Citric acid               .050                                                                          1.000                                               Fluid Preparation (May be painted on full strength, or                        diluted with water for use as a rinse)                                                                  % by weight                                         Ethanol, USP              15.00 -Polysorbate 80 0.20                          Flavoring oils            0.50                                                Glycerin                  5.00                                                FDC Red No. 3             .25                                                 FDC Blue No. 1            .50                                                 Water, q.s. ad            100.00                                              Aerosol Sprays                                                                                          % by weight                                         Glycerin                  15.0                                                Ethanol, absolute         43.4                                                Saccharin                 0.1                                                 Flavor                    0.2                                                 Propellant 12             16.0                                                Propellant 114            25.0                                                FDC Red No. 3             0.1                                                 FDC Green No. 3           0.2                                                                           100.0                                               Ethanol, USP              20.00                                               Glycerin                  5.00                                                Flavoring oils            0.35                                                FDC Red No. 3             0.25                                                FDC Green No. 3           0.50                                                Water                     68.90                                               Propellant 12             5.00                                                                          100.00                                              Lozenges                                                                                                Grams                                               Corn syrup solids, spray dried                                                                          .880                                                Flavoring oils, spray dried with modified starch                                                        .050                                                Calcium stearate          .010                                                FDC Red No. 3             .020                                                Hercules Green Shade 3    .040                                                                          1.000                                               ______________________________________                                    

What is claimed is:
 1. A composition in the form of an aqueous solution,aerosol spray, chewable tablet, wafer or lozenge for application to theoral cavity for accomplishing the differential disclosure of dentalplaque, said composition consisting essentially of FDC Red. No. 3 andFDC Green No. 3, said FDC Green No. 3 being present in from about 0.1 to4 parts by weight for each part by weight of the FDC Red No. 3, saidcomposition differentially staining areas of old, thick accumulation ofdental plaque blue and thin, recent deposits of dental plaque red,whereby effectively practiced plaque removal on a given tooth shows, andcan be photographed, as either no stain pickup or thin deposits stainingred, while certain areas on said tooth if consistently missed, will beconsiderably thicker and therefore stained blue, and on some teeth, anintermediate definite purple zone can be distinguished between the redand blue areas, said intermediate definite purple area tending to lookmore like blue plaque than red plaque, but the thickness of this purpleplaque being less than that of blue plaque, while tooth surfaces notcovered with plaque do not show the dye at all.
 2. The composition ofclaim 1 further including a surfactant.
 3. The composition of claim 1wherein said composition is in the form of an aqueous solution.
 4. Thecomposition of claim 1 wherein said composition is in a chewable tabletor wafer form.
 5. The composition of claim 1 wherein said composition isin aerosol spray form.